We have been making RNA from mouse adipose tissue recently for PCR &
northerns. We remove adipose tissue from the animals and store it at -80. We
then process 0.5 gm following the Trizol (Life Technologies) protocol. There
is a lipid interface that needs avoiding when removing the aqueous phase. I
never bother re-extracting the organic phase although that should increase
yields somewhat. After precipitation and re-suspesion in water, this
typically yields about 200 ug of total RNA. We then purify this on OligotexdT
(Qiagen) and routinely get about 10 ug of polyA+ material. Both total and
purified material look excellent on a gel and blot well with control probes.
We have also succesfully PCRd a number of full length cDNA products from this.
Hope this helps, good luck.